The
46-year-old Beck, who retired from the Seal Team 6 only months before
it raided Osama bin Laden's hideout, explains that she decided to
undergo hormonal therapy some time after leaving the service in 2011.

Beck served 20 years as a Navy SEAL, including seven combat deployments, earning a Purple Heart and Bronze Star.

As The Atlantic Wire notes,
Kristin, who works as a military consultant in Florida, decided to come
out by posting a new picture of herself dressed as a woman on her
LinkedIn profile.

"I am now taking off all my disguises and letting the world know my true identity as a woman," Beck wrote.

In
the memoir, Beck notes the irony of one mission as a SEAL in which he
is disguised as an Afghan man to blend in with female-hating Taliban
men.

"It was weird that I could grow a beard and trick them into
thinking I was one of them -- and really I'm an Amazon woman in disguise
as a U.S. military guy in disguise as a Pashtun!"

The book is
dedicated to his family, to the "underdogs, the activists, the
downtrodden," and to his SEAL teammates, to whom he offers a personal
message: "I am still the same person with the same experience and the
same spirit."

The memoir, published by Advance Press, notes that
Beck has been married twice and has two sons, but removed himself from
their life because of his frequent deployments and a wish to avoid
dealing with his own issues.

The book includes some reactions from
this former team members, including praises for Beck's courage in the
forward, which was written by former boss, retired Navy SEAL and
astronaut William Shepherd.

Other comments from former Navy SEAL teammate:

"Being a SEAL is hard. This looks harder."

"I am thankful that your decision was to confront your challenges
rather than, as you stated in your own words, 'put a shotgun in your
mouth.'"

"You're a Team Guy, first and foremost, and you always
will be. I'll drink a beer with you anytime, anywhere, for any reason,
no matter how you are dressed ... especially if you are buying."

The Virginian Pilot, which serves a largely military area of Virginia, writes
that transgender service is still forbidden in the military, even after
the repeal of "Don't ask, don't tell" opened the military up to gay and
lesbian servicemen and women.

Beck's co-author is Anne Speckhard,
an adjunct associate professor of psychiatry at Georgetown University
Medical School, whose has specialized on post-traumatic stress disorder
and counterterrorism.